WASHINGTON (AP) — Under pressure to do more for hurricane-ravaged Puerto Rico, President Donald Trump is waiving federal restrictions on foreign ships’ transportation of cargo to the island.

White House press secretary Sarah Huckabee Sanders said on Twitter Thursday that Trump has authorized a waiver for the U.S. territory for a little-known federal law that prohibits foreign-flagged ships from shuttling goods between U.S. ports.

She said Trump was responding to a request from Puerto Rico Gov. Ricardo Rossello, and that the Jones Act waiver “will go into effect immediately.”

Advocates who pressed for the waiver have said it could get desperately needed supplies delivered to the island more quickly and at less cost.

Hurricane Maria hit Puerto Rico more than a week ago and has left it without power and with little access to fuel and other supplies. Republicans and Democrats had urged Trump to waive the Jones Act.

Acting Homeland Security Secretary Elaine Duke had waived the law earlier this month to help ease fuel shortages in the Southeast following hurricanes Harvey and Irma. That order included Puerto Rico, but expired last week shortly after Maria struck.

The Trump administration had said a waiver was not needed for Puerto Rico because there were enough U.S.-flagged ships available to ferry goods to the island.

Trump told reporters Wednesday that his administration was looking at a new waiver, but he said, “We have a lot of shippers and a lot of people and a lot of people that work in the shipping industry that don’t want the Jones Act lifted.”